ocm-helm-toolbox

This is a toolbox for bundling Helm charts into OCM component versions (in CI), and later unpacking from that format for a deployment (in CD).

Unlike other OCM-based workflows, this toolbox is specifically designed to not require extra operators to be installed in the target Kubernetes cluster. All that you need is a Helm CLI.

Staging area for the sapcc/ocm-helm-toolbox. Build with make.

Installation

From the cloned repo, the application can be built with make and installed with make install. The helm and ocm commands must be installed for the toolbox to do its work.

Help

$ ocm-helm-toolbox --help
Toolbox for deploying Helm charts with OCM

Usage:
  ocm-helm-toolbox [command]

Available Commands:
  add-timestamp-to-version Adds a build timestamp to the given chart's version.
  bundle                   Prepares a component constructor for a Helm chart.
  completion               Generate the autocompletion script for the specified shell
  help                     Help about any command
  unbundle                 Unpacks a Helm chart from an OCM component version.

Flags:
      --debug     print more detailed logs
  -h, --help      help for ocm-helm-toolbox
  -v, --version   version for ocm-helm-toolbox

Use "ocm-helm-toolbox [command] --help" for more information about a command.

$ ocm-helm-toolbox add-timestamp-to-version --help
Adds a build timestamp to the given chart's version.

This is useful when you want to upload multiple bundles of a Helm chart
to an OCM store without having to bump the chart version for each change.

Usage:
  ocm-helm-toolbox add-timestamp-to-version <helm-chart-directory> [flags]

Flags:
  -h, --help   help for add-timestamp-to-version

Global Flags:
      --debug   print more detailed logs

$ ocm-helm-toolbox bundle --help
Prepares a component constructor for the given Helm chart, for consumption by "ocm add componentversions".

To make the bundle hermetic, all images referenced by the Helm chart should be declared with --image-relation. For example:
    --image-relation ".Values.db_metrics.image.repository is repository of quay.io/prometheuscommunity/postgres_exporter:0.16.0"
    --image-relation ".Values.db_metrics.image.tag is tag of quay.io/prometheuscommunity/postgres_exporter:0.16.0"
    [and so on]

Images so declared as related to the Helm chart will be bundled into the OCM component version, and transported inside it.
On unbundle, a localized-values.yaml file will be rendered which overwrites the declared value paths to refer to the bundled images.

Usage:
  ocm-helm-toolbox bundle <helm-chart-directory> [flags]

Flags:
      --component-name-prefix string   (required) A prefix that will be prepended to the name of
                                       the first Helm chart to form the overall component name.
                                       Usually looks like a URL path element, e.g. "example.org/".
  -h, --help                           help for bundle
      --image-relation stringArray     A declaration of the form ".Values.<path> is <repository|digest|tag|reference> of <docker-image-ref>".
                                       See command documentation above for what this declaration causes.
                                       The option may be given multiple times to include multiple declarations.
                                       A single option may also contain multiple declarations, separated by commas.

                                       References to ${ENVIRONMENT_VARIABLES} in exactly this one form are replaced with the respective variable's value.
                                       After that, $(command substitutions) in exactly this one form are replaced by the output of the command.
                                       Command substitution does not understand any quoting or nested shell syntax.
                                       Only a list of bare words is supported, like "$(cat version.txt)".
      --provider-name string           (required) The provider name value for the component metadata.

Global Flags:
      --debug   print more detailed logs

$ ocm-helm-toolbox unbundle --help
Unpacks a Helm chart from an OCM component version created by the "bundle" subcommand.

The component version can be given either as the path to a CTF archive on the filesystem,
or as a fully qualified reference into an OCI registry, in the form "$OCI_REGISTRY//$COMPONENT_NAME:$COMPONENT_VERSION".

If the component version contains image relations, a file "localized-values.yaml" is rendered
into the output directory. This file must be given to Helm with the --values switch.

If the Helm chart carries a "cloud.sap/git-location" label, its contents are written
into the output directory under the file name "git-location.json".

Usage:
  ocm-helm-toolbox unbundle <component-version> <target-directory> [flags]

Flags:
  -h, --help   help for unbundle

Global Flags:
      --debug   print more detailed logs